The latest issue of Bloomberg Businessweek focuses on the potential impact of the Affordable Care Act lawsuit that heads today to the U.S. Supreme Court for oral arguments. Joshua Green spotlights one particularly interested person who has bucked the trend of remaining silent about the possible implications of the plaintiffs winning King v. Burwell.

A notable exception to this monkish silence is Stuart Butler of the Brookings Institution in Washington. Butler, 67, is the Zelig of modern health-care reform, present at every critical stage. In 1993, as a scholar at the conservative Heritage Foundation, he designed a health-care plan around an individual mandate that became the main alternative to the Clinton administration’s plan. A decade later, when he soured on the mandate, many conservatives followed suit. President Obama’s decision to make the mandate a pillar of the ACA ignited broad conservative antipathy to the idea, which left Butler, its progenitor, awkwardly situated when Heritage became the locus of opposition. His decision last July to leave Heritage after 35 years and move to Brookings is a gauge of how far Republican health-care policy has moved to the right since the Clinton era.

Practically alone among Republicans, Butler is sounding an alarm about what a decision in favor of the King plaintiffs would carry with it. While Democrats would be dismayed if the court guts Obama’s signature initiative, Butler’s worry is grounded in an understanding that voters with skyrocketing premiums may not blame Obama, as Republicans assume. They’ll expect the party hellbent on destroying the law to have a solution—and react badly if none is forthcoming. Because 16 states operate their own exchanges and therefore won’t be affected by the court’s ruling, Butler believes the ACA will stagger on and eventually recover, since voters won’t abide a system wherein some states have affordable, federally subsidized health-care coverage and others do not. Absent an alternative, he says, the ACA will rise again like a horror-movie killer. “People who believe the ACA instantly goes away are deluding themselves,” he says. “By not doing anything to develop a Republican vision of how to move forward, they could end up with the very nightmare they’re trying to avoid.”